Method of purifying hydrocarbon compounds



March 27, 1934 original Filed Maron 24, 192s INvEN on ATTORNE? PatentedMar. 27, 1934 UNITED STATES PATENT o FFICE MET'HOD 0F PUmFYiNGHYDROCARBON COMPOUNDS Original application March 24, 1925, Serial No.17,855. Divided and thisy application May 19,

1930, Serial No. 453,638

1o claims. (ci. 19t-96) This invention relates to the treatment ofhydrocarbons and the distillates thereof by polymerization of unstable,unsaturated compounds present in such hydrocarbons. It involvesimprovements in means for carrying on the process described in myPatent, No. 1,340,889 granted May 25, 1920 and in my pendingapplications, Serial No. 664,893 led September 26, 1923 and 17,855,filed March 24, 1925 of which this application is a division; andparticularly, it involves means for improving the operation of thoseprocesses and for facilitating the removal of the spent catalyst fromapparatus used therein.

It will be understood that in carrying on the said process, thehydrocarbons to be purified are rst vaporized and then passed in vaporform into and through a chamber containing solid adsorptive treatingmaterial such as fullers earth, capable of selectively polymerizing theunstable, un-

' saturated compounds. In treating hydrocarbons, such as crackeddistillate or so-called cracked gasoline, kerosene, etc., to removeunstable,y unsaturated compounds, such as dioleflns and-the like, it isfound that with the passing of vapor through the adsorptive material adeposit of gum or other adhesive material forms thereon which tends tocoat and adhere to the surface of the adsorptive material and sointerfere with its action and gradually impair the effectiveness of theprocess until finally the adsorptive material is rendered so farineiectual that it becomes spent, so that it must be burned or otherwiserevitalized in order that it may be restored to condition for use.Diiliculties have been yexperienced in removing spent adsorptivev`material from the chamber due to the fact that the foreign materialsdeposited therein during the treatment of the hydrocarbon vapors are.gummy and adhesive so that the adsorptive material tends to sticktogether in masses and to form lumps which prevent easy removal of thetreating material. It is of great importance in the practical use of theprocess in (connection with other refinery apparatus that the activityof the treating material be prolonged to the maximum and the timerequired for emptying and recharging the treating tower should be cutdown to the minimum in order to reduce delay and interfere as little aspossible with the operation of the other apparatus.

I have discovered that by introducing a solvent in small quantities intothe treating tower for the purpose of washing out the treating materialreferred to, I am able to improve and prolong the effectiveness ofthe'adsorptive material and to level of liquid in the bottom of thetower and the overcome the tendency thereof to form into lumps and clog.By this means, I am able to keep the adsorptive material in suchcondition that it may quickly and easily be removed from the treatingtower. ,i

Objects of my invention are to provide for carrying on the processesdescribed in the aforementioned patent and applications moreeconomically and eiectually and to provide for rapidly discharging theadsorptive material from the treating tower when such material hasbecome spent, so that the apparatus may operate longer on a singlecharge and may be out of operation on account of discharging andrecharging for the least possible time. H0

Other objects, novel features and advantages of this invention will beapparent from the following specification and accompanying drawingwherein is illustrated one form of apparatus for carrying on theinvention.

.A still 10 of ordinary construction and set in brickwork is heated byre or otherwise in the usual manner. The still may' be provided withsuitable connections (not shown) for supplying fresh oil and withdrawingresidual oil in order that distillation may be carried on continuously.It is connected by a vapor line 11 with the inner chamber of adouble-walled tower 13, the inner wall of which terminates above thebottom of the tower. A'screen 14 is provided within this 85 i manhole1'7 is provided adjacent the screen 14.

A vapor discharge pipe 18 leads from the upper 90 portion of the annularchamber of the tower 13 to the condenser 19 which in turn communicateswith the run down tank 20. The pipes 11 and 18 are provided with valves21 and 22 respectively.

"A trapped pipe 23 controlled by a valve 24 9 leads from the bottom ofthe treating tower into the still tank. A trapped pipe 25 controlled bythe valve 26 communicates with the tower at a point slightly above thelower edge of the inner wall and leads to the still 10. The pipe 23provides means for draining the treating tower and the valve 24 isnormally kept closed. The pipe 25 provides means for maintaining aconstant valve 26 normally is open. The level of the liquid in thebottom of the tower is suchthat the lower edge of the inner wall of thetower projects below the surface of the liquid, thus forcing vapor topass through the liquid in order to get into the annular chamber and outthrough the discharge pipe 18.

In the top of the inner chamber there is provided a ring 27 throughwhich cooling fluid' may be circulated. There is also provided a spray28 by means of which liquids may be introduced into the inner chamber.

In the operation of the apparatus above described vapors from the still10 are conducted through the pipe 11 into the inner chamber of thedouble walled tower and are caused to pass downwardly through theadsorptive material 15, under the lower edge of the inner chamber wall,

upwardly through the annular chamber and outA through the discharge pipe18 to the condenser and run down tank 20. These vapors containunsaturated, unstable hydrocarbon compounds which are polymerized by theadsorptive material to form polymers of higher boiling point whichliquefy in the adsorptive material and drain through the screen 14 intothe bottom of the treating tower. The process likewise results in thedeposit of gum and other foreign and adhesive matter in the adsorptivematerial so that ultimately the polymerizing action is substantiallyinterfered with.

To prolong the life of the treating material, I pass a quantity ofsolvent through the adsorptive material for the purpose of dissolvingand removing with it foreign matter as well as expediting the drainageof the polymers, thus keeping clean the surface of the adsorptivematerial so that it is free to exercise its adsorptive effect on thepassing vapors. Any suitable solvent may be employed, but I have foundthat condensate from the vapors is generally satisfactory for thepurpose. This condensate may be obtained by so regulatingthe temperatureand pressure of the process that a portion of the vapors in the innerchamber will condense within the inner chamber and iiow through theadsorptive material. The pressure and hence the temperature of thevapors passing through the tower may be regulated by means of the valves21 and 22.

Such solvent also may be supplied from a source (not shown) to the sprayhead 28, or condensate may be obtained within the chamber by passingcooling uid through thering 27. Irrespective of the manner in which thesolvent is introduced into the chamber it dissolves foreign matter andconveys the same in liquid form together with polymers through thescreen 14.

In the bottom of the tower is contained a body of liquid which hasdrained from the treating material and which seals the lower end of theinner chamber. This body of liquid is kept at a predetermined level bymeans of the overflow pipe 25. The treated vapors pass through this bodyof liquid and are washed and scrubbed by their passage through the same,after which they are conducted by the pipe 18 to the condenser 19. The`passage of the vapors through the body of liquid in the bottom of thetower removes from the vapor any entrained liquid such as polymers orcondensate, thereby insuring a liquid product of stable color andfurther prolonging the effective life of the treating agent.

, The process may be practiced with apparatus other than that abovedescribed and changes may be madein the structure of the apparatuswithout departing from the spirit of the invention. For example, asingle shfl tower such as is also shown in my application, Serial No.17,855 may be utilized by suitably arranging the piping so that thetreated vapors are caused to pass through a pool of liquid in the bottomof the tower.

I claim:

1. The process of treating hydrocarbon oils to effect separationtherefrom of undesirable unsaturated compounds of substantially the sameboiling point which comprises polymerizing said unsaturated compounds toform compounds of higher boiling point by continuously passing the oilin the vapor form through a solid adsorbent catalytic material at suchtemperatures that a portion of the vapors are condensed to liquid andare passed downward throughthe catalytic material, dissolving therefromadsorbed polymers and continuously maintaining the activity of thecatalyst, and subsequently passing treated vapor through a body ofliquid obtained from the treating material.

2. The process of purifying cracked hydrocarbons which consists inpassing the same in vapor form through a body ofv solid adsorbentmaterial thereby depositing on the said material a polymerized compoundwhich tends by its presence to render the said material ineffectual andremoving the said compound during operation of the process by passage ofa condensate of the said vapors through the said material, collectingliquid draining from treating material and passing treated vapor throughsuch liquid. l

3. The process of purifying cracked hydrocarbons which consists inpassing vapors thereof into contact with a solid adsorbent material toinduce polymerization of unsaturated constituents thereof andcoincidently passing a liquid soll vent of the polymers through suchmaterial, and subsequently passing treated vapor through abody of liquiddrained from the treating material.

4. 'Ihe process of purifying cracked hydrocarbons which consists inpassing the same in vapor form through a body of solid adsorbentmaterial, thereby depositing on the said material a polymerized compoundwhich tends by its presence to render the said material ineffectual,condensing a portion of the vapors in the presence of the 1 saiddeposited compound to form a liquid capable of dissolving the same andpassing the said liquid through the said material thereby continuouslywashing out the said deposited compound and revitalizing the saidmaterial, collecting liq- 1 uid draining from treating material andpassing treated vapor through such liquid.

5. The process of purifying cracked hydrocarbons which consists inpassing the same partly in. liquid and partly in vapor form into contactwith 1 a solid adsorbent material to form polymers from unsaturatedconstituents of such hydrocarbons and continuously dissolving thepolymers in and removing them from the said material with the liquidportion of the said hydrocarbons, and sub- 1 sequently passing treatedvapor through a body of liquid drained from the treating material.

6. The process of purifying cracked hydrocarbons which consists inpassing-the same in vapor form through a body of solid adsorbentmaterial l thereby forming in the said hydrocarbons certain high boilingpolymerized compounds, maintaining the said material at a temperaturesuch asv toa produce condensation of a portion of the entering vapors,passing the condensate through the said 1 material to therebysubstantially remove the said compounds and separating the vapors andliquids emerging from the said material, collecting liquid draining fromtreating material and passing treated vapor through such liquid. 16(

7. The process of purifying cracked hydrocarbons which consists inpassing the same in vapor form through a body of solid adsorbentmaterial thereby depositing on the said material a polymerized compoundwhich tends by its presence to render the said material ineffectual andthen removing the said compound by passing a liquid solvent thereofthrough the said material, and subsequently passing treated vaporthrough a body of liquid drained from the treating material.

8. The process of purifying cracked hydrocarbons which consists inpassing the same in vapor form into contact with a body of solidadsorbent material thereby depositing a polymerized compound on the saidmaterial, regulating the pressure of the said vapors in the presence ofthe said material in such manner as to produce condensation of a portionthereof and passing the condensate through the said material tosubstan-= tially remove the said compound and revitalize the saidmaterial without interruption of the process, collecting liquid drainingfrom treating constituents thereof, collecting liquid draining from theadsorbent material and passing the treated vapor through such liquid.

T1510 T. GRAY

